Trackway system for train control



March 13, 1945.

M. T. WINTSCH TRACKWAY SYSTEM FOR TRAIN CONTROL Filed sept. 3. 1941 3sheets-sheet i March 13, 1945. v M. T. wmTscH.

TRACKWAY SYSTEM-FOR TRAI CONTROL Filed Sept. 5, 1941 3 Sheets-Sheet'Z umN N mum@ 111|! Ill wmw|1|| l hun llllll! .U m .m x ILT qkm. MIKQEMII.HLL,||111| FiledSept. 5, 1941 3 Sheets-Sheet 5 Patented Mar. 13, 1945TRACKWAY SYSTEM Fon TRAIN- CONTROL Max Theodore WintschLancaster, Pa.,assignor of fifty-one per cen't to Newton M. Weaver,

Lancaster, Pa.

Application september a, i941, serial No. 409,335 v 15 claims. l(c1.246-63) This invention relates to a trackway system adapted particularlyfor use where the traic is light rolling stock, such as subway trainsand suburban cars, and where there are relatively short block sections.By this invention high speed loperation of such traffic will be entirelysafe and feasible.

" i One of the objects of'myinvention is to provide a trackway systemwhich will supply control currentfor a four indication cabsignaL'utilizing the track rails and an auxiliary trackway conductorcircuit to convey the controlcurrent.

Another object of my invention is to provide a system in which the blocksections maybe dividedinto so-callecl main and intermediate blocksections and control current may be independently flowed in the trackrails and auxiliary trackway conductor circuits of keach or-theymay be'interlocked as desired Vto indicate varying l'traffic conditions. l

This invention is also concernedwith the .pro-

vision of adequatesafeguards to insure that any failure of the equipmentwill result intheeffect ing of a restrictive condition indication in` thcab signal, insuring against accident. i v i According to thisinvention, the track rails are divided into block sections, each ofwhich includes a main block section and, at the exit end of each blocksection, an intermediate block section. Electrical circuits are providedfor impressing control current upon the track rails in the main andintermediate block sections in accordance with traffic conditions inadvance block sections. An auxiliary current conductol` is provided inthe intermediate block sections and ex- Eg.,

`tends into or throughl the main yblockysections. Electricalcircuits areprovided for the energiza- ,tion-of the conductors and these circuitsare like- Wise controlled by advance traflic conditions, thevintermediate and main block auxiliary trackway conductor circuits beingindependently controlled. Preferably, afsingle pick-up transformer isprovided on thevehicle to be controlled and this'is effective forreceiving the current in the rails and in the auxiliary trackwayconductor-'circuits and suitable signalling and controlling equipment isprovided to translate the current received by thepick-up transformerfrom the rails and the auxiliary trackway conductor circuits intosignals and/or controls. y

' Inorder that my invention may be'easily understood, I-Will describethe same in conjunction with the attached drawings, in which,

Ams

FigureZ is a diagram illustrating the flow of vcontrol current in thetrack railsand auxiliary ,trackway conductor circuits andshows thesignal indications effected-when avehicle occupies an advance' mainblock section,

fFigure 3 is ya similary view showing a vehicle in an advanceintermediate `blcck section, y

`Figurei shows a still further traffic condition with vehicles in bothrnainy and intermediate block sections, and l N f Figure 5 is aschematicjlayout of a typical cab signal and-control arrangementwhichmay be operated by the track system'shvow'nin Figure l.

,THnTRAcK'CnicUrrs Referring to Figure l, the track'rails are di. videdinto a plurality of `main or primaryl block sections, main sectionsA'afn'd B beingshown. AAt the exitend of each mainvblock section,v anintermediate `block nsection is' provided. In the drawings, intermediateblock sections B' and C are shown. The exit end of block jA, which isnot shown, would include a similar intermediate block section.Therailsin each section A, B,'B andA C are insulated kfifo'm'the 'railsinthe next adjacent section, theinsulation 2 being diagrammaticallyshown in the drawings. Each block section,'therefore, constitutes anelectrically insulated current.conduct ing 'portion of trackage for therreceptionof train control current.

In `describing the trackk circuit arrangement,

reference will belmade primarily to main blockv section A, which is,occupied by a vehicle V,.main block section B, and intermediate blocksection B'. Each main and intermediate block section will be similarlyequipped and, accordingly, corresponding numbers have beenappliedto theminor'portionof Athe track and control relays for block section B, shownin Figure l; for convenient understanding ofthe invention.,

Each main and intermediate block section is provided with a vhighvoltage transformer 3, supplied with current from atransmission line 4to which the primary `5jof the transformer .3 is permanently connected.Eachy main block ,section is'provided with a track transformer 6 andeach intermediate block section with a similar track transformer 1. TheAprimaries 8,and `9, respectively', `of saidr track transformeraone sideof eachvof which ispermanently connected to secondary loofthehighvoltageftransformer 3, are fed withcurrent frornthe'sec'ondary I0only when predetermined track conditions existQvas will be more fullyhereinafter described; The. second aries Il and I 2 ofthe tracktransformers E and 1 are permanently connected to the track rails in themain and intermediate block sections, respectively. In each main blocksection, the secondary I! is connected through leads I3 and I4 and ineach intermediate block section the secondary I2 is connected across thetrack rails by leads l5 and I6. In other words, the primaries of thetrack transformers are controlled to eiect the supply of current to thetrack rails, the secondaries being permanently connected to the trackrails.

Each main block section is provided with a track relay TR. (a lettercorresponding tothe block section letter has been added to each .relayin the track circuit). Likewise, each .main .block section is providedwith a control relay CR. The intermediate block sections are providedwith track check relays TIR and safety relays SR..

The track relays TR are effective for controlling the supply ofsignalling or control current to the 'track rails Ain the next rearwardadjacent intermediate block sections. The control relays CR aresimilarly eiec'tive for controlling the supply of such current to thetrack rails in the next rearward main block sections. This will beapparent `from an examination of Figure 1 Where track relay' TRA,through its 'ar-mature l1, when energized and elevated into engagementYwith front point of contact 'l1' (it is shown in deenergized and`lowered position?, connects the controll'edside of the primary 9 yoftrack transforn'ier 1 for 'intermediate `block `section B', with thesecondary l0 lof high voltage `transformer 3, through leads +B, 19 and20. same manner, control relay CRA, through its armature 21, connects`the primary 8 of track transformer 6 circuit with the secondary lil ofhigh voltage transformer 3, through leads 18 and 22 armature 23 of relayIRA.front point of contact 24. lead '25, .armature 26 ofV track checkrelay "IIRB, front point of contact 21 and leads 28 and 29.

By this means, .the supply of control current to the track rails of eachof the main and intermediate block sections .is electrically'controlledin accordance with existing traffic conditions.

Extending throughout each intermediate block section .and into theexitend at least of each main block section is an additional means for'supplying control current. This is in the form of an auxiliary trackwayconductor circuit including a 'conductor bar 3U, having sections a andb, connected together by a choke coil 3l.. The length of the bar 30h ineach main block section will depend upon the type of rolling stocknormally using the trackage and its normal operating speed, as well asthe length of the main block sections. In .many instances, if the barextends one thousand feet, into the main block section, it will -provideadequatewarn'ing of conditions in theinterinediate block sections topermit safe operation, even under abnormal weather and other conditions.It is desirable, however, to extend the bars throughout substantiallythe entire length of the block sections or, if less than the entirelength, to provide adequate right-ofway signals to indicate the exacttrack conditions.v The bars 30 are preferably of insulated copper orother current conducting wire and are Epiked or otherwise secured,insulated against ground, to the cross ties. Each bar, when electricallyconnected-constitutes a loop upon which current may be impressed. f

Each intermediate block section has a. motor alternator set'32 or othersimilar device for sup- In the l plying control current to the trackwayconductor circuit. This set includes a motor 33 and an alternator 34adapted to supply alternating current of say 100 cycles at 30 volts whenthe motor is in operation. The trackway conductor section 301) isnormally connected to the alternator 34 by leads 35, 36, and 31, so thatwhen the motor .alternator set 32 is in operation, current of 100 cyclesfrequency flows through the trackway conductor section 33h. The trackwayconductor section 30a is controlled bythe track relay in the nextadvance main blocksection as will be hereinafter described. Unlikesection 30h it is not permanently connected to the alternator to beenergized whenever the alternator is in operation, but only when thetraic conditions in the next advance block are such that the applicationof control `current thereto is proper.

, Operation of the motor alternator set 32 is lcontrolled by track relayTR of the next advance 'block section. A source S of low voltagecurrent, say lcycles at 120 Volts, extending along the right-of-way,provides current for the motors yof the respective motor alternatorsets, one side of each motor 4being normally connected to the linethrough a lead 38. The other side of the source S connects by lead 39with armature 40 of track relay TR and a lead 4I `connects to the otherside of the motor 33, the circuit being complete when armature 4l! fallsinto engagement with contact point 42 to which lead 4l is connected.

Relay CR 'is fa direct current relay and is utilized as a control, beingrendered inoperative in the event of any failure of the auxiliarytrackway conductor circuit. This is eilected in 'the following manner: Abattery 43, or 'a rectifier if preferred, is connected to one side ofthe rel-ay CR through lead 44. A 'lead 45 from the other side of thebattery connects with lead 3B joining with the bar 33a. vChoke coil 3lwhich will pass direct current connects bars 30a and 3011. Lead 35' fromthe conductor 301; connects with leads '46 and 41 extending to a chokecoil 48 which blocks the alternating current and connects by a lead 49to the relay CR. Ablocking condenser BC is `provided in lead 35 of theauxiliary trackway conductor circuit to prevent the passage of directcurrent from the battery 43 of the control relay Acircuit into thecircuit of the alternator 32, while at `the same time permitting thefree passage of alternating current to the auxiliary trackway'conductorcircuit. The circuit traces from battery 43 through leads 45 and 36, barsection 30a, choke coil 3|, bar section 30h, leads 35, 46 and 41, chokecoil 48, and lead 49 to the relay CR. If there be any break in theauxiliary trackway conductor circuit, therefore, relay CR will bedeenergized and its armature 2l will fall. interrupting the circuit forthe supply of control current to the track rails in the next rearwardmain and intermediate block sections, effective to initiate a suitablesignal or control or both.

l,To insure that the battery will always be fully charged, a tricklecharger 50 may be provided which is supplied with current from thesource S.

Track check relay TIR is also eiective for controlling the supply of4signalling or control current to the track rails in the next adjacentrearward main block section. Thus, when track relay TRA is deenergized(as shown in Figure l) and set 32, through lead 4I.

point of contact 5I andcurrent -rom the secondary VIIJ of high voltagetransformer liiowsv through lead I8, larmature`2l,-lead 22, armature 23,back point of contact 5I of relay TRA, a lead 52 to armature 53 of trackcheck relay-TIRB, a point of contact 54, lead a point of contact 56which is-engaged by armature 51 of safetyy relay SRB and a lead 58 whichconnects with lead29 to the primary 8 of tracktransformer 6 for blocksection B.

By this arrangement, current is fed to the track rails in the nextrearward main block section (main Yblock sectionv B, for example) when avehicle occupies the next advance block section (main block section A asshown in FigureL l);

Track check relay TIR, like track relay TR, is controlled by conditionsexisting in the intermediate block section across the railsrof which it`is electrically connected, although it is also controlled by relay'I'RA as will be brought out. l

Safety relay SR is provided in each intermediside of the secondary I Il,is normally connected to the other side of relayTIRB through leads 62,66

' .and I5. to the track rail to. which relay TIRB is intermediatesection 36a ofthe auxiliary trackate block section so that, in the eventof failure of the alternator 32 for any reason, the supply of `thecontrol current for the nextv rearward main block section Will beinterrupted.. Referring to Fgcurrent source S through lead 38. Armature51 of relay SRB is thus elevated into engagement with point of contact56, closing the circuit for the supply of current to the track rails ofmain block section B through control of 'primary' ofA track ,transformer6. The circuit is fromsecondar'ydll of high voltage transformer 3,through lead I8, point of contact 6|, armatureZI, lead 22 to armature 23of relay TRA, point of contact5l lead 52, l.

armature53 ,of track check relay TIRB, .point of contact 54, lead 55,point of contact l56,- and arma- -f ture 51 of safety relay SRB andleads 58 and 29 to one side of the primary 8. vThe other side oftheprimary 8 is normally connected to the secondary I Il of the highvoltage transformer 3 by lead 62. f

Thus, when a vehicle occupies an advance niain block section controlcurrent for the track rails in i the next rearward main block will owtherein so long as the alternator remains in operation.

Should the alternator fail `for any reason or should the current'supply' for track check relay TIR lfail because of abroken rail or anobstruction in the intermediate blocksection to which it is connected,safety relayA SR-will be deenergized and control current in thecorrespondingmain block'will fail; resulting in the establishment of aWarningl signal in any vehicle occupying or entering the main block, aswill be hereinafter described.

Armature lI1 of track Vrelay TRA is provided with a back point ofcontact 63 which is elTective for controlling the flow of current totrack-check relay TIRB in the event of .deenergization of track relayTRA. The circuit is from the secondary I Il of high Voltage transformer3 through leads I8 'and I9, armature I1, backA point of contact 63, aresistor l64 effective for reducing the current to that suicient foroperation of track check relay TIRB, and lead 65 to the relay The otherThe other connected by lead 61.`

ldeenergized relay TIRB will remain energized Thus, when relay TRA isunless the current lsupply through the rails of the ,intermediate blocksectionis rshunted out, 'for example, by a vehicle occupyingintermediate blockfsection B. f

Track relay TRA is provided with a fourth armature 68 which is effectivewhen relay TRA is -deenergized for Vcompleting the circuit for the Wayconductor, circuit. The circuit is from alternator 34, through blockingcmdenSerBC, leads 35, 46 and 69 to-armature` 68, point of contact 16 andlead 1I to one side of the trackway conductor 'section 36a.v The otherside ofthe conductor 30a is. normally connected to the other side of`the alternator through lead 36.

Track check relay TIRB is provided vthird.armaturen which is electiveforr energizing the motor alternator "32 when relay TRA.

- whichno-rmally controlsitupon deenergization,

'ure' 1, the safety relay SRB is shown in energized position, it beingconnected by leads 59 and'lilll vacross the leads 36 and 46 from thealternator'34.

is lenergized and relay TIRB is deenergized by .reason of a vehicle inintermediate section B', for

example. AUnder such conditions, armature 12 falls into lengagementwithpoint of contact 13 and .current is then fedv from source S throughleadIII, armature 12, point of contactl13, and a lead 1,5 to oneside ofmotor y330i` the motor alternator32. The other Vsideof the'm'otor isnormally connected tothe source 31.by lead'38. By this arrangementcontrol current is fed to trackway Vconductor Asection 3Ilb when avehicle occupies the intermediateblock section.

Assuming now that` a vehicleV is operating in lblocksectionfA and movingin the direction of the arrow, the? Supply of currentfor tracktransforr'ner 1 will be interrupted in the following manner: The vehicleV will shunt vout vthe current supply-'for the track relayTRA WhichIiscon- Ane"cte d'a`.cros's the rails of main block section A, in

which 'the vehicle-V is'operating.` Armature I1 vr(as well as all thearmatures) will thereupon fall andthe current supply for the primary 9of track transformer 1, which is fed from the secondary If of the vhighvvoltage transformer 3 through leadsV I8` and IS, armature I1, and pointof'contact `I 1', connectedv with lead 20 from the primary 9 of tracktransformer1, will be open. j

y mediate blockl sectional?l and the rails in intermediateblock section`B'Y will vnot be4 energized WhenV a vehicle occupies block A.

Af Armature I 1 will, however, fall into engagement` with point ofcontact 63 and current will thereupon be fed to the track checkv relayTIRB through vthe circuit from secondary II), through` leads I8 andl I9.armature I1, point of contact 63. resistor 64 and lead 65 to relay TIRB.The other side of this relay is normally connected to 'the 4othersidevof the secondary I0 through a lead 61 to Aone of the track rails andfrom the track rail by leads I5 and 6,6. 'l

Thus, relay TIRB will be energized even though no current is flowing inwinding I2 of trans'- rformer 1 which supplies currentto the rails towith a' check relay but also the resistor circuit as well. While thevehicle occupies block A and track relay TRA is de'energized,v armature40 connected with lead 39 from' the source of low Voltage current 31,will be in contact with pointl of `contact 42 which connects throughlead 4l to motor 33 of the motor alternator set 32. `The motor 33 will,therefore, be in continuous operation and` alternating current 100cycles per second will be fed finto the trackway conductor sections 30aand 30h. 'This is effected in conductor 30a through blocking condenserBC, leads 35, 46 and 69, armature 68 of relay TRA, point of contact 10and lead 1l. The other side of trackway conductor section 30a' isnormally connected -to the alternator 34 .by lead 3S. Trackwayconcluctorsection 30h is normally connected to the alternator 34 so that when thealternator is in operation current of 100 cycles frequency is fed to thetrackway conductor section 36h. This circuit is through blockingcondenser BC, and lead 35, trackway con ductor section 30h, lead 31 andlead 36 to the other side of the alternator.

Thus, when a vehicle occupies block A, current of 100 cycles per secondfrequency will be impressed upon the trackway conductor sections 30a and3th of intermediate block section'B'. p

The rails of main blocksection B `will be supplied with current fromtrack transformer B (this may be alternating current of 140 cycles at 30volts). This is eected by lead 62 from one side of the secondary l ofhigh Voltage transformer 3 to one side of the primary 8 of tracktransformer 6. The other side of the secondary is y connected to theprimary 8 through lead 18, point of contact 6I oi armature 2l of controlrelay CRA, lead 22, armaturel 23 of' track relay TRA, back point ofcontact l,lead 52, armature 53 oftrack check relay TIRB, contact 54,lead55, point of contact 55, and armature'l of safety relay SRB, andleads 58 and 29.

Thus, 'the track rails in main block section B will be energized withalternating current of.140 cycles when a vehicle occupies block A.

Since track control current Will beflowing in main block section B-when.block A is occupied, as previously described, track relay TRB will beenergized and track control current will besupplied to intermediateblock section C. No current Will be ilowingin the auxiliary trackwayconductor circuit of-interrnediate block section C', however, sincetrack relay TRB is eiective for energizing the circuit for the motoralternator set for that block section only when relay TRB isdeenergized. Also, track controlcurrent will be supplied tomain blocksection C since armature Il of track relay TRB- which corresponds torelay TRA Will be in engagement with a point of contact il', closing thecircuit for the primary 8 of the track transformer 6 which suppliescurrent to the rails of main block section .C (not shown) in the samemanner as TRA when it is energized. v

Similarly, no current vWill be owing in the trackway conductor sectionof main block section C since the check relay TIR for that block will beenergized by the control current supplied from its track transformer. c.l

Thus, when a vehicle occupies blockA, block sections C and C will havecurrent of 140 cycles per second frequency impressedupon their trackrails and no current will be flowing in' their respective trackwayconductor sections.

Recapitulating the conditionstexisti-ng in the M afin block section A(a) yCurrent shunted by vehicle V causing de-l energization of the trackrelay TRA (b) No current in the auxiliary trackway conductor circuitIntermediate block section B (a) No current in the track rails.Nevertheless, relay TIRB remains energized by current from Winding l0,through register 64 (b) Current of cycles frequency in the auxiliarytrackway conductor circuit Main block section B (a) Current of cycles4frequency in the track rails (b) Current of 100 cycles frequency in theauxiliary trackway conductor circuit AIntermedicne block section C" andmain block section C (a) Current of 140 cycles frequency in the trackrails (b') No current in' the auxiliary trackway conductor circuit.

Now assume that the Vehicle occupies' inter mediate block section B'; asshown in Figure 3, instead of main .block section A and also bearingin'mind the showing of Figure l. This vehicle Will shunt out winding I2supplying current for track check relay'TIRB, causing armature 2 6 whichcontrols the supply of current to -tracktransformer 5 to fall and nocontrol current will flow in the track rails of main block section B.Armature 'l2 of relay TIRB Will fall into engagement with point ofcontact 13, completing the circuit for the motor alternator 32 whichwill thereuponsupply current to the track- Way conductor section4 30h ofmain block section B. .Since there is no control current in the rails ofmain block section B, relay TRB will fall and the alternator forintermediate block section C' will be set in operation, supplyingcurrent to the loop circuit. Since there is no vehicle in main blocksection A, track relay TRA which controls the energization of theauxiliary trackway con- .ductor circuit for intermediate block section Bthrough armature 'I0 will be energized and the circuit for the trackwayconductor of inter-mediate block section B Will be open and no currentwill ow therein.

Under such conditions-a vehicle occupying intermediate blocksection Band no vehicle' in main block section A, the control and signallingcurrent in the track and auxiliary trackway conductor circuits will beas follows:

Intermediate block section B' (a) Current shunted by vehicle V causingdeenergization of checkrelay TIRB (b) No current in the auxiliarytrackway conductor circuit l Main block section B (a) No current in thetrack rails v (b) Current oi 100 cycles frequency in the auxiliarytrackway conductor circuit Intermediate block section C (a) Current ofA140 cycles frequency in the track rails o (b) Current of 100 cyclesfrequency inthe auxiliary trackway conductor circuit. Referring now toFigure 4 Where a vehicle V occupies main block section A and anothervehcle X'isffollowing in overlap block section Bf,

the conditions are yas follows: Vehicle V shunts out relay TRA; armature40 completes the circuit for motor alternator 32 and armature 68completes the circuit for the loop circuitin overlap block section B.vVehicle Xshunts out relay TIRBand armature 26 whichk controls the s upply of current for track `transformer 6 willbe openl-no current will beimpressed ori-.the track -rails of main block section B. Relay TRB willthereupon open, itsarmatureV falling into engagement vwith pointofcontact 63 completing thecircuit forothe track check relay for`intermediateblock section C (in' the samemanner as rent impressed-uponthe track railsand the relay |53 being responsive to alternating currentof `100r cyclesper second corresponding to' the current -impresseduponthe various loop circuits. .(These reed relays are Well known andaremore particularly described in my United States Patent-No.12,105,134'.)` yCurrent from a 'battery source |56 is fed to avacuum tube amplifier I5| and,

Whenfeither of thev relays |52l or |53 lis .in vibra--v tion,r currentis `fed to control relays;n

"Referring .to the recapitulation of :conditions existingin thetrack-,andloop circuits `with main block section A occupied by a vehicleand referring v to Figure 2, it will be observed lthat intermediatepreviously` described in connection with Figure 2 whererelay TRA isopen). Armature 'l2 of relay TRBwill complete the circuit for thealternator for overlap block section C andcur'rent Will .flow intheauxiliary rtrackway conductor circuit for overlap block `section C.

The track and auxiliary 'trackway conductor circuit conditions will be:e

y n Main block section A Y (a) Current shunted by vehicle yV causingdeenergization of track relay TRA (mNOcunent in the auxiliarytrackwayconductor circuit i Y -Intermedicteblock section 13A (a)vCurrent of 140 cycles frequency in'A the track rails (b). Current of`100 cycles frequencyin the auxiliary trackway conductor circuit.V

THE CAB CIRCUITS The cab signalarrangement shownin Figure 5 will'fnowbe'consiclered.

Suspended onthevehiclea distance ahead of the first pair of Wheels'above therails an'dl on the side adjacent the bar (Figure 5), there isblock section C has current of 140` cyclesy frequencyy impressed uponthetrack rails but 'no current rin;the;auxiliary trackway conductorcircuit. Relay |52 is responsive to alternating current of a frequency140 cycles per secondand isytherefore,in.vibration Whena vehicle entersloverlap block section'C" with main block section A- occupied. Grid |58of .vacuum tubel'l is thereby inuenced-resulting infa oWPof currentthrough control"1elay.|til; Relay |60i's connected -to battery -|56byleadslGI" and |62. The other side of relayii i's'connected to theplate-cathode circuit|59byl1ead |63; `1 7- `2=flWhen relay-|60 isenergized, its armatures/Will `3.0 'all' be elevatedas shoWnin Figure;Its arma- 'S4-Will engage'front point of contact |65 carrying?currentfrom the battery |56 through leadsl |62 ller; lucana m te signa iightrsa "-niay- -loelcoloredr green. The otherside vof llllfgiArrnaturel'lDwill engage front point of contact I'H and will complete a circuit fromthe towakjpoint of;contact` |13 of signal'relaylflll, through armaturey|15 `'of.`.S g1f1al relay |14 and oft'whichisfconnected'to the 'powersource |56 through ground by leadw|`|8. The solenoidvalve I lflfis thusnormally energized andi/s elective for l closing .the airj supply lineto the ,alarmY whistle |199@ i'gIf vthe train be electricallyvoperated,` a holding coil lmay be provided effective forholding thecircuit-breaker for thefmain power supply4 in closed'position. Ifthis beemployed, armature Il lll Will, be Supplied =on signal relay and this iwillf'clo'se'the front point of contact|62 connectedby" lead`f|83 to onesideof the holding coil l'lthufsljsupplying current to the holding' coilljflro'rngth'e battery |56 through' the leads |62, |6|fand|66. The otherside of the holdingvcoil is.

w ground connection.

provided .a pick-up transformer |50 which is adapted to receivebyinduction thecurrent iinv pressed upon the rails or upon the 4loop 3 0,The

currentrso induced is fed to an amplier |5| vand from there to a pair ofvibrating reed relays ,|52 and |53. The relays are tuned by condensers|54 and |55 respectively so as tovigorously .vibrate when-current*,-isinduced in the pick-up transformer` |50 and passes through theampliiier to,

the` relays |52 andv |53; the relay |52y being responsive to alternatingcurrent of afrequency of lfiQ- cycles per second,corresponding-taglinecurj the vo oe rator will .,getjfa green,l or clear signal indicationVas Vhis -vehicle moves through intermediate block section Cf Q When theVehicle -mo'vesV intothev zone thev loop circuit of nain-block section;B, however, current'of 100 cycles frequency is'flowing in the auxiliarytrackway conductor circuit as .Well as the cycle current in the trackrails. The current in thelocpv circuit will be picked up inductively by`the pick-up transformer |50 and after lpassing-through the amplifierwill energize 'reed relay |53Which is tuned to l100` cycles per second.

When reed -relay |53 is. in'vibration;` current will beifed to* gridx|84inthe radio ltube resulting in a f ,iow ofjcurrentfthrough' thtubesthe'fs' i"gxnalli'ght"V |68 is connectedv directly y,to thebattery'al56"`throughgground connection by lead connectedfto the powersupply |56 through plate-cathode i circuit |85, energizing control`relay |14. Thus, current vwill `ow from the power source |56 throughleads |62, |6|, |66, and |86rfrontipoint ofcontact |81, armature. |88and lead |89 to a signal light |90 which may be colored yellow. Theother side of the signal light |90 is connected to the power source |56through ground connection by lead |69. i 1

Since 140 cycle current is also owing inthe rails of main block sectionB, reed relay |52. will also be in vibration and the green signal lightwill be illuminated so long as the vehicle continues to move throughmain block sectionB.

Thus, with block A occupied, a train moving through main block section Bwill get a clear indication (green), if the loop circuit does not extendthroughout the extent of main block section B, until it reaches the zonecontrolled by the auxiliary trackway conductor circuit whereupon it willget an approach medium 4signal (green over. yellow) indicating to theoperator that he should approach at medium speed.

When they vehicle Vpasses from main block section B into intermediateblock sectiony B' the green signal light will be extinguished since thetrack rails in that section are not' energized and an approach signal(yellow over red) will be given in the following manner: Since currentof 100 cycles per second is still owing in the auxiliary trackwayconductor circuit of intermediate block section B', the yellow lightwill remain illuminated, current being supplied in the manner justdescribed for main block section B. There is no control current inthetrack rails of intermediate block section B', however, and relay |52will not be energized. Asa consequence, control relay |60 'will bedeenergized .and its armature |64 will Vfall, completing the circuit fora signal light which may be coloredred. The connection is from armature|64., back point of contact |9| and lead |92 tothe signal light |93, theother side of which is connected to the power source |56 through groundconnection by lead |69.

The supply of current for thefsolenoid valve |11 will/likewise beinterrupted since amature will be elevated away from the back'point ofcontact |13 breaking the circuit from the power source |56. Likewise theholding coil |80 will hel deenergizedby reason of the dropping ofarmature |8| away from front point of contact |82 which connects theholding coil tothe power source |56@ A reset Vbuttonl |94 may beprovided which is eiective for connecting the holding coil |90 and thesolenoid valve |"11'with thepower source |56 when the button |94 isbrought into engagement with the contacts |95 andv |96 com.- pletingvthe circuit from the power source |56 through leads |62 and |91 tocontact |95, through button |94 to contact |96, and through lead |98 tothe holding coil, and lead |99 (shown in dotted lines, since it may beoptional) to the solenoid valve |11. The yellow and red signals willcontinue to be illuminated so long as the vehicle rails in intermediateblock section B' are not energized, even though the reset button be heldin engagement.

When the vehicle enters block section A which is already occupied by thevehicle V, there will be no current flowing in the rails for it has beenshun-ted out by the vehicle V. Thus neither relays |52 and |53 -will bein vibration and both relays |60 and |14 willbe deenergized. This willbring armature |64 into engagementI with back point Armature |8| willdrop away from front point of contact |82 thus interrupting the supplyof current for the holding coil and the main circuit for the supply ofcurrent to the driving motors, if the engine be electrically driven,will be interrupted.

Should the operator desire to continue move-l ment of the vehicle, hemay manually operate the reset button |94, thus energizing the holdingcoil |30 and the valve |11. The danger signal will continue to beilluminated, however, so long as the vehicle carrying the signallingequipment is occupying the same block as another vehicle or the supplyof current to the track rails is nterrupted for any other reason;

The cabsignals appearing in a vehicle approaching occupied main blocksection A would be:

Intermediate block section C: Green-clearproceed at full speed Mainblock section B: Green over yellow-approach medium-approach next signalor indication point at notexceeding medium speed Intermediate blocksection B: Yellow over redapproach-prepare to stop at next signal orindication point. Reduce to low speed.

Main block section A: Red-danger-stop at OnCe.

The cab signals which would be given for the other conditions are shownin Figures 3 and 4 where the cab signal designations have been shownover the various block sections.

Assuming that all blocks are unoccupied, relay TRB will be energizedsince it is only deenergized when the supply of current is shunted outby a vehicle in block B or when the current is shunted out of the trackrails in intermediate block section B causing relay TIRB to fall andinterrupting the supply of track relay current to main block section Bat point of contact 21. When relay TRB is energized no current flows inthe auxiliary trackway conductor circuit for intermediate blockvsectionC since the supply of current to that circuit is controlled by arma`ture 12 of relay TIRB which is elevated away from its back point ofcontact 13 and by armature 40 of relay TRAwhich is elevated from itsback point of contact 42. There is, therefore, train cab control currentflowing in the track rails of all block sections and no train cabcontrol current flowing in the trackway conductors. Thus a vehiclemoving along the trackway would continuously exhibit a green orlclear-proceed at'v full speed signal.

Should there be any failure of any auxiliary trackway conductor circuit,control relays CR will be deenergized. They are direct current relaysreceiving current through the auxiliary trackway conductor circuits inthe manner pre' viously described. When any control relay CR isldeenergized, the circuit for the track current in the next rearward mainblock section will be opened and since no current will then be flowingauxiliary treackwayv By providing such relays provision is made for yadequately safe-guarding against'any failure of the equipment for uponsuch failure a morere'- stricted condition is indicatedthan actuallyex.-V l

Thel particular type .of ca-'o signalequipment is not important solong'as it isdesigned to translate the currentin the'track rails andauxiliary trackway conductor circuits into proper signals and/orcontrols. :The reed vrelay type equipment isparticularly well adaptedfor use with this invention.

By the terms control and train control as used in the specification andthe claims I mean to include signals which indicate to the vehicleoperator the proper control to be effected as well' as direct mechanicalor electrical control as in the device described above where the'brakesvof the vehicle' are controlled. Likewise by the term different currentas used herein in distinguishing the auxiliary trackway conductorandftrack currents, I intendto include alternating currents of diiferentfrequencies, alternating and direct current, alternatingand pulsatingdirect current, and thelike. i I I i While I have illustrated anddescribed certain preferred embodiments ofl my invention, the same isnot limited to those described and illustrated but all other embodimentswithin the scope of the following claims: i

Iclaim: l. ..l f r- 1. .A trackway systemf for train control in tracks.divided into block sections comprising means for impressingtrain controlperiodically varying current of one'frequency upon Ythe track rails ineach blocksection only when the next advance block section is clear, anauxiliary trackway conductor disposed within a portionvat leastl of eachVblock section, and means for impressing train control. periodicallyvarying current of a 4second frequency upon the conductor in 'said block`section only when the nextor secondedvance block section is not clear,said currents of dilerent characteristics flowing in said track railsand conductor respectively; either simultaneously-or in one or the otherdepending upon`v advance traffic conditions.

2. A trackway system for train control in tracks divided into blocksections comprising means for impressing train control periodicallyvarying cur-v rent of one frequency upon the track rails of veach blocksection only when the 'next advance block section is'clear, an auxiliarytrackwayV conductor disposed within a'portion at least of each block;

simultaneously when'the said next advance block section is clear but thesecond advance block sectiondsnotclean. iy 1.1.1.

.3.;Atrackwaysystem for train controlin tracks divided into blocks eachincluding a main and an intermediate section comprising means forimpressing train-control periodically varying 7 currentl of'onefrequency uponthe track rails in a 'section onlyV when the next advancesection is clear, an. auxiliaryv trackway conductor in the intermediate`section and a similarpconductor in the. exit end at least of the mainsection, means, for :impressing tra-in control periodicallyk varyingcurrent ofl a second rfrequency upon the conductor in the next rearwardmain or intermediate A section when the adjacent advance section isf`not clear, and means for impressing saidcurrents ofdiiferentcfrequencies .onto Asaid rails and conductor respectively, in arearward main lor in.- terniediate block section when the adjacentadvance section is clear butthe second advance section is not clear. l ii @4.A trackway system for train control in tracks divided intorblock.sections comprising means forimpres'sing train control periodicallyvarying current of one frequency Vupon the track 'rails' of each blocksection. when the next advance block section is clear, an auxiliarytrackway conductordisposed within-a portion at least ofeach`block'section, means for impressing train control periodically varyingcurrentof another vfrequency upon' 'said kauxiliary trackwayconducto-nwhen said next or second advanceblock section is not clear,currents of different frequencies flowing inv said track rails andconductor respectively, sin multaneously erin one Ior vthe other'depending' uponladvance tra'ic conditions, a train carried pick-up:transformer for receiving said'4 currents, and train lcarriedmeansresponsive to said train control currents for initiating signalsindicat-I upon said `auxiliary trackway conducto-r when said'next orsecond advanceblock section is, not A clear,A currents of dilferentfrequencies flowing in said track rails'A and conductor. respectively,simultaneouslyl or "in one orthe other depending upon'fadvance trafficconditions, a train carried pick-up transforr'ner for receiving-saidcurrents, train carried means responsive to said train control currentsfor initiating signals indicating traffic conditions, and a traincarried.L receiver including means for translating said track currentinto one signal indication, meansfor translating said; yauxiliarytrackway conductor currentv into va second signal indication, and meansopera-v tiveupon'the failure of said track current for initiating athird signal. l

6. A trackway system for train control in tracksl divided intoelectrically insulated Ymain andoverlap'block sections comprisingmeansfor impressing train control periodically varying current of onefrequency upon the track rails in the main and overlap block sections:in accordance with' advance traffic conditions, auxiliary trackway"conductors disposed within said intermediate blocksections andthe exitend at leastof.

saidmain" block (sections, 'means for impressing traincontrolperiodically varying current'fof' a secondfrequency upon theauxiliaryKA conductors in the main and overlap block sections inaccordance .with advance tralc conditions, a track relay responsive tothe flow of said train control current in said main block section andeffective for controlling the Supply of train control current tothetrack rails in the next rearward intermediate block section, a trackcheck relay responsive to the iiow of said train control current in saidintermediate block' section and effective for controlling the supply oftrain control current to the track rails in the next rearward main blocksection, and a circuit controlled by said track relay for supplyingenergizing current to said track check relay when the track relay inlthe next advance main block section is deenergized.

7. A trackway system for train control in tracks divided intoelectrically insulated main and overlap block sections comprising meansfor impressing train control periodically varying current of onefrequency upon the track rails in the main and overlap block sections inaccordance with advance traliic conditions, auxiliary trackwayconductors disposed within said intermediate block sections and the exitend at least of said main block sections, means for impressing traincontrol periodically varying current of a second frequencyy upon theauxiliary conductors in the main and overlap block sections inaccordance with advance traiiic conditions, a track relay responsive tothe flow of said train control current in said main block section andeffective for controlling the supply of train control current to thetrack rails in the next rearward intermediate block section, `a trackcheck relay responsive to the liow of said train control current in saidintermedia-te block section and effective for controlling the supply oftrain control current to the track rails in the next rearward main blocksection, a source of high voltage current; and a resistor and a circuitcontrolled by s'aid track relay for supplying cur-rent from said sourcethrough said resistor for energizing said track check relay when thetrack relay in the next advance main block section is deenergized.

8. A trackway system for train control in tracks divided into blocksections comprising Ameans for impressing train control periodicallyvarying current of one frequency uponthe track rails in one blocksection, an auxiliary trackway conductor disposed within said blocksection, an alternatorvfor supplying train control periodically varyingcurrent of a different frequency to the conductor in said block section,either simultaneous with'or separate vfrom the supply of said trackcurrent, land means for controlling the supply of either frequencycurrent to their respective railsfor conductors, including a trackcurrent re-y sponsive relay in an advanceblock section controlling thesupply of track current and conductor current to rearward block sectionsto provide conductor current only in the first rearward block sectionand track and conductor current simultaneously in the second rearwardblock section when said advance block section is not clear. y

9. In a trackway system for train control in tracks divided into mainand intermediate block sections, auxiliary trackway conductors in saidsections connected together by a choke coil for the passage of directcurrent therethrough, a circuit for supplying alternating current tosaid trackway conductors, a direct current relay for initiating arestrictive control in a rearward` block section upon deenergization ofsaid control relay through failure of saidA auxiliary trackway conductorcircuit, a circuitv for the supply of direct current for energizing saidcontrol relay, said circuit Vbeing completed through said conductors andchoke coil, and a blocking condenser sections, auxiliary trackwayconductors in said sections connected together by a choke coil for thepassage of direct current therethrough, a

l circuit for the supply of train control current in a rearward blocksection, a direct current relay in said circuit for initiatingarestrictive control in said rearward block section upon deenergizationof said control relay through failure of said auxiliary trackwayconductor circuit, a'

direct current into the alternator.

1l. A trackway system for `train control in tracks divided intoelectrically insulated main' and overlap block sections comprising acircuit for supplying train control periodically varying current of onefrequency to the track rails in the main and intermediate blocksections, a track relay responsive to the current in the main blocksection and controlling the supply of train control current to the trackrails in the next rearward intermediate block section, a track checkrelay responsive to the current in the intermediate block section andcontrolling the supply of train control current to the track rails inthe next rearward main block section, auxiliary trackway conductorsdisposed within the main .and intermediate block sections, an.alternator for supplying current of a second frequency to the trackwayconductors, a circuit controlled by said track relayand said track checkrelay to initiate said alternator upon deenergization of either of saidrelays, a circuit permanently connecting the auxiliary trackwayconductor in the main block section to said alternator, and anindependent circuit controlled by the track relay in the next advancemain section connecting the auxiliary trackway conductor in theintermediate block section to the alternator to provide for the ow ofcurrent only intheauxiliary conductor when the next advance blocksection is not clear, in the rails and conductor respectively,simultaneously when the next advance block section is clear but thesecond advance block sec-` tion is not clear, and only in the rails whenat least two sections in advance are clear.

l2. In a trackway system for train control in tracks divided intosections, an auxiliary trackway conductor, means for supplying currentof one frequency to the track rails, an alternator for supplying currentof a different frequency to the conductor, a safety relay forcontrolling the V supply of current to the track rails in a rearwayconductor, means for supplying current of one frequency to the trackrails, an alternator for supplying current of a different frequency tothe conductor, a track relay connected to the rails and responsive tosaid current of one frequency, a safety relay for controlling 'thesupply of current to the track relay in a rearward block section toinitiate a restrictive control through said track relay in the event offailure of said alternator, and a circuit for supplying current fromsaid alternator to energize said safety relay only so long as saidalternator is in operation.

14. In a trackway system for train control in tracks divided intosections, an auxiliary trackway conductor, means for supplying currentof one frequency to the track rails, means for sup-- plying current of a`different frequency to thel conductor, and a safety relay energized bysaid current of different frequency for controlling the operationof arelay in a rearward block section to initiate a restrictive control insaid rearward block section in the event of failure of said means forsupplying current o f a different frequency to said conductor.

15. A trackway system in accordance with claim 3-`in which the means forimpressingtrain I control periodically varying current of a secondfrequency includes an alternator for supplying current of a frequencydifferent from the current supplied vto the track rails.

' MAX THEODORE WINTSCH.

